11 May 2016 Current Affairs: NASA’s unmanned Kepler space observatory has discovered the largest trove of exoplanets outside our solar system. So far, it has discovered total of 1,284 exoplanets and it is more than double the number of known exoplanets found with the Kepler space telescope. Of the new trove of 1,284 exoplanets nearly 550 are said to be rocky planets like Earth, based on their size. The new discovery has given hope that eventually another Earth can be discovered. So far NASA has discovered nearly 5,000 total planet candidates, of them more than 3,200 have been verified and 2,325 of these were discovered by Kepler.
Kepler space observatory : The unmanned Kepler space observatory was launched in 2009 and was tasked with determining how commonly, Earth-like planets occur throughout the Milky Way galaxy. Since then it has scanned nearly 150,000 stars for signs of orbiting bodies, particularly those that might be able to support life. The Kepler observatory works by observing a dimming in the light of a star, known as a transit, each time an orbiting planet passes in front of it The observatory has been designed for a statistical mission and not to probe into the environmental conditions of planets that exist in the so-called Goldilocks zone of their stars.
Exoplanet : It is a planet that does not orbit the Sun and instead orbits a different star, stellar remnant, or brown dwarf. It is also termed as extrasolar planet.
Goldilocks zone : It refers to a habitable zone in the planetary system where the temperature is neither too high nor too low. Such conditions could allow for the presence on the planet’s surface of liquid water – a key ingredient for life.